The present invention relates to a floating platform having a body for displacing water when submerged at a depth which is not or little disturbed by surface waves. More particularly the invention relates to such a platform wherein float columns extend from a submerged body float and are interconnected by a rigid, horizontally extending frame.
Floating platforms with two, parallelly oriented submerged floats are known and these floats carry columns functioning as additional water displacing floats carrying the platform above the sea level. Sometimes the platforms can be vertically displaced on these columns. These platforms with submerged floating body are easily maneuverable and can readily be transported to their destination point, but the two parallelly disposed displacement elements or bodies react to a significant extent to underwater currents and are difficult to maintain in position. This is particularly so if these platforms are used for offshore drilling. The basic reason for this lack in positional stability must be seen in that the submerged bodies exhibit different characteristics as to stability in longitudinal and transverse directions.
Other types of floating platforms are known wherein the submerged floating body is of annular configuration, and the central, open space has an auxiliary platform for resisting vertical movements of the body. This submerged control platform may have openings with means for closing, so that controlled water flow can traverse the platform in either direction. The principle platform above sea level is strutted or otherwise secured to the submerged floating body.
This latter construction has the advantage of isotropic stability and resists vertical displacement to a very significant degree. This annular construction has, however, the disadvantage that the entire pay load including fuel and other provisions to be consumed have to be stored on the main platform so that the center of gravity of this arrangement is rather high and that in turn is disadvantageous as to floating stability.